RotoZip RZ20-4200 5.5 Amp Variable Speed Spiral Saw 5.0 amp, variable speed (15,000 to 30,000 rpm) motor provides precise control of cutting speed when cutting a variety of materials Industry's first three-jaw chuck eliminates use of collets, allowing for quick, easy, and wrenchless bit changes Metal Bezel strengthens spindle lock mechanism for longer tool life; dust-sealed switch; plastic adjustable foot; quick-release detachable handle Includes 1/8-, 5/32-, and 1/4-inch collet and collet nut, also for use with Zip Bits and new XBITS Limited warranty